P2E89: Proximity Detection Circuit B Low

What it means

The proximity detection circuit B (SAE J1772 PD signal) reports a low condition. Charging cable plug detection is impaired.

At a glance

• Usually lights the check-engine light

How it works

Proximity detection circuit B carries the SAE J1772 signal that lets the charging system recognise a plug at the inlet. The control module monitors its signal level; this code sets when circuit B is detected below its expected low limit, which can result from a wiring fault or poor contact at the inlet.

Common causes

Most likely first.

1. Charge inlet contacts dirty
2. Wiring fault

Symptoms

• Check-engine or charging-system warning light
• Charging may not start or may be interrupted

How to diagnose it

1. Review freeze-frame data and read live proximity circuit B data while inserting the charging plug.
2. Check whether the inlet fails to recognise the plug or loses recognition during a charging attempt.
3. With charging disconnected, inspect the inlet contacts and circuit B connector for dirt, corrosion, damaged pins, or a loose fit.
4. Inspect accessible proximity circuit B wiring for a short, chafing, or damage that could pull the signal low.
5. Test circuit B signal and continuity against the manufacturer's wiring information and specification.

Common fixes

• Clean the inlet contacts using the vehicle's approved method.
• Reconnect loose circuit B terminals and repair poor contact.
• Repair damaged wiring that is pulling the proximity signal low.
• Replace a confirmed faulty inlet or proximity-detection component.

Can I keep driving?

The vehicle can usually be driven, but charging may not start or may stop because the plug is not detected. Do not force the connector into place; use another charging option until circuit B is repaired.